闽江河口养虾塘水体可溶性有机碳、营养盐和叶绿素a浓度变化特征

Variation of DOC,nutrients and chlorophyll a contents in shrimp ponds of Minjiang River Estuary

为揭示河口区陆基养虾塘可溶性有机碳(DOC)、营养盐、叶绿素a时空动态变化及其生态化学计量特征,在福建省闽江河口鳝鱼滩选择3个陆基养虾塘作为研究对象,于2018年5-10月原位测定养虾塘水温、pH、盐度、溶解氧指标,并采集不同深度水样,实验室测定DOC、可溶性无机氮(DIN)、磷酸盐(PO43--P)、叶绿素a浓度,探讨其主要影响因素。结果表明,养虾塘水体中DOC、DIN、PO43--P和叶绿素a质量浓度分别介于5.73~16.79 mg·L-1、0.04~1.80 mg·L-1、0.03~0.16 mg·L-1和15.02~443.08μg·L-1,均存在明显的时空变化特征;养虾塘水体DOC、营养盐、叶绿素a浓度受到养殖水体水环境参数、人为活动、养殖生物的共同影响;养虾塘水体碳(C)、氮(N)、磷(P)营养元素组成与植物、土壤之间具有相似性,并且表现为碳盈余和氮限制。在养殖过程中,加强对养虾塘水体营养盐和叶绿素a的动态变化监测,通过人为方式调节养虾塘水体C、N、P比率,对于防止养虾塘水体富营养化,促进养虾塘生态系统绿色可持续生产具有重要作用。

In order to reveal the spatiotemporal dynamic changes of DOC,nutrients,chlorophyll a and their eco-chemical metrological characteristics of land-based shrimp ponds in the Minjiang River Estuary,Fujian Province,from May to October 2018,we have analyzed the water temperature,pH,salinity,dissolved oxygen.The soluble organic carbon(DOC),soluble inorganic nitrogen(DIN),PO43−-P and chlorophyll a mass concentration were 5.73−16.79 mg·L−1,0.04−1.80 mg·L−1,0.03−0.16 mg·L−1 and 15.02−443.08μg·L−1,respectively,all with obvious characteristics of spatio-temporal changes.The concentrations of DOC,nutrients and chlorophyll a were affected by the water environment parameters,human activities and cultured organisms.The water nutrient composition of carbon,nitrogen and phosphorus was similar with that of plants and soil,showing carbon surplus and nitrogen limitation.In summary,In the process of aquaculture,it is very important to strengthen the monitoring of the dynamic changes of nutrients and chlorophyll a in shrimp ponds,and artificially adjust the ratio of carbon,nitrogen and phosphorus,so as to prevent eutrophication of shrimp pond and promote the green and sustainable production of ecosystem of shrimp ponds.